WO2014188906A1 - Near infrared oxygen concentration sensor for palpation - Google Patents

Abstract

Provided is an oxygen concentration sensor for palpation by which the contact of the sensor with a site to be measured is ensured so that the oxygen concentration (oxyhemoglobin concentration, deoxyhemoglobin concentration, degree of oxygen saturation, etc.) at the site can be surely measured, while minimizing effects on palpation performance. A near infrared oxygen concentration sensor (1) for palpation that is to be attached to the finger pad in the tip side of the first joint of a user's finger, said near infrared oxygen concentration sensor (1) comprising a base material (2) to be attached to the finger pad, a light-emitting means (4) which is formed on the base material and irradiates a target with light of at least two wavelengths including infrared light, light-receiving means (5a and 5b) which are formed on the base material and receive measurement light coming from a light-emitting device via the target, and a light-shielding means (3) which is positioned at least between the light-emitting means or the light-receiving means and the finger pad and prevents the measurement light coming via the user's finger to enter the light-receiving means, wherein the minimum distance between the light-emitting means and the light-receiving means is 3 mm or more and the maximum distance between the same is 15 mm or less.

Description

触診用近赤外酸素濃度センサNear infrared oxygen concentration sensor for palpation

　近赤外光を用いて、人体内の酸素化ヘモグロビン濃度、脱酸素化ヘモグロビン濃度及び酸素飽和度の少なくともいずれか１つを測定する近赤外酸素濃度センサに関する。特に、触診時に用いるのに適した構造を有する触診用近赤外酸素濃度センサに関する。The present invention relates to a near-infrared oxygen concentration sensor that measures at least one of oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration, and oxygen saturation in a human body using near-infrared light. In particular, the present invention relates to a near-infrared oxygen concentration sensor for palpation having a structure suitable for use during palpation.

　分娩時や陣痛等のストレスにより、胎児が低酸素血症に陥り胎児機能不全となることがあり、重篤な場合は新生児低酸素脳症になって脳性麻痺に至ることもある。したがって、胎児の酸素動態をモニタリングすることは胎児の状態を知る最善の方法である。非侵襲的に酸素飽和度を測定する従来技術として近赤外線分光法があり、この近赤外線を用いて胎児の酸素動態を経腟的に見る方法は過去に試みられてきた。具体的には、破水後、４ｃｍ長の送光部と受光部のセンサを子宮頸管に沿って通過させ胎児の頭部から前額部に装着する方法が知られている（特許文献１）。● Stress such as labor and labor may cause the fetus to fall into hypoxemia, resulting in fetal dysfunction, and in severe cases, neonatal hypoxia encephalopathy may lead to cerebral palsy. Therefore, monitoring fetal oxygen dynamics is the best way to know fetal status. Near-infrared spectroscopy is a conventional technique for measuring oxygen saturation in a non-invasive manner, and methods have been attempted in the past to visually observe the oxygen dynamics of the fetus using this near-infrared ray. Specifically, a method is known in which a 4 cm long light transmitter and a light receiver are passed along the cervical canal and attached to the forehead from the head of the fetus after water breakage (Patent Document 1).

　しかしながら、子宮内にセンサを挿入すると感染などの危険性の問題、また胎児の前額部にうまく接着しないことも多いこと、また分娩の進行に伴って胎児が下降しセンサがずれてしまい測定できなくなってしまうことなど問題点も多く、臨床応用に至っていない。胎児皮膚へ簡便、確実に装着できる方法、さらに胎児の下降に関係なく測定できる方法が求められている。また、子宮内の胎児の酸素濃度の測定のほか、体腔内（口腔内や直腸など）の部位や、手術中の部位（心臓など）の酸素濃度を簡便かつ確実に測定する方法が求められている。However, when a sensor is inserted into the uterus, there are many problems such as infections, and it often does not adhere well to the forehead of the fetus. There are many problems such as disappearance, and it has not reached clinical application. There is a need for a method that can be easily and reliably attached to fetal skin and a method that can be measured regardless of fetal descent. In addition to measuring the fetal oxygen concentration in the uterus, there is a need for a simple and reliable method for measuring the oxygen concentration in body cavities (in the oral cavity, rectum, etc.) and during surgery (heart, etc.). Yes.

　近赤外酸素濃度センサの場合、センサと被検体表面との確実な接触が極めて重要であり、体外から測定する技術は多く知られているが（特許文献２、３）、これらの技術をそのまま体腔内部位の測定に用いることは困難である。また、触診時に用いられる診断装置として触診用超音波診断装置が知られているが（特許文献４）、センサ自体が大きく触診の操作性を損なわずに用いることは難しい。また、超音波では酸素濃度を測定することはできない。
　特許文献５には、容積脈波を求めるために、手指に光センサを取り付ける技術が記載されている。しかしながら、特許文献５は、触診部位の酸素濃度を測定するものではないため、複数波長光源や使用者の手指側の酸素濃度情報の遮断などについて記載されていない。また、特許文献５は血圧計であるため、圧力センサが必須である。In the case of a near-infrared oxygen concentration sensor, reliable contact between the sensor and the surface of the subject is extremely important, and many techniques for measuring from outside the body are known (Patent Documents 2 and 3). It is difficult to use for measurement of a body cavity site. Further, an ultrasonic diagnostic apparatus for palpation is known as a diagnostic apparatus used at the time of palpation (Patent Document 4), but it is difficult to use the sensor itself without losing the operability of palpation. In addition, the oxygen concentration cannot be measured with ultrasonic waves.
Patent Document 5 describes a technique for attaching an optical sensor to a finger in order to obtain a volume pulse wave. However, since Patent Document 5 does not measure the oxygen concentration at the palpation site, it does not describe the blocking of the oxygen concentration information on the multi-wavelength light source or the user's finger side. Moreover, since patent document 5 is a blood pressure meter, a pressure sensor is essential.

特開平０４－２２６６３９Japanese Patent Laid-Open No. 04-226639国際公開２００７／１３９１９２International Publication 2007/139192国際公開２０１２／１１５２１０International Publication 2012/115210特開平０２－３０７４３７JP 02-307437特開２００６－２３９１１４JP 2006-239114 A

　特許文献１に示された胎児用のパルスオキシメータは、外部から子宮内にセンサを挿入するものであるため、胎児皮膚に確実に接触させることが難しく、また感染などの危険性がある。特許文献２及び３に示された近赤外酸素濃度センサは体外から測定するものであり、そのままでは体腔内の部位の酸素濃度の測定には使うことができない。特許文献４に示された触診用超音波探触子は、超音波を用いた診断であり、体腔内の部位の酸素濃度を測定することはできない。また、特許文献４では指先の大きさに比べて比較的大きな超音波探触子を指先に取り付ける構造であるため、触診の操作性を損なってしまう恐れがある。The pulse oximeter for fetuses disclosed inPatent Document 1 inserts a sensor into the womb from the outside, so that it is difficult to reliably contact the fetal skin and there is a risk of infection and the like. The near-infrared oxygen concentration sensors disclosed inPatent Documents 2 and 3 are measured from outside the body, and cannot be used as they are for measuring the oxygen concentration at a site in the body cavity. The ultrasonic probe for palpation disclosed inPatent Document 4 is a diagnosis using ultrasonic waves, and cannot measure the oxygen concentration at a site in a body cavity. In addition, sincePatent Document 4 has a structure in which an ultrasonic probe that is relatively large compared to the size of the fingertip is attached to the fingertip, the operability of palpation may be impaired.

　本発明は上記問題点を解決するためになされたものであり、触診の操作性への影響を最小限にしつつ、測定対象部位へのセンサの接触を確実にして、当該部位の酸素濃度（酸素化ヘモグロビン濃度、脱酸素化ヘモグロビン濃度、酸素飽和度など）を確実に測定する触診用酸素濃度センサを提供することを目的とする。The present invention has been made in order to solve the above-described problems, and while ensuring the contact of the sensor with the measurement target site while minimizing the influence on the operability of palpation, It is an object of the present invention to provide an oxygen concentration sensor for palpation that reliably measures oxyhemoglobin concentration, deoxygenated hemoglobin concentration, oxygen saturation, and the like.

　上記課題を解決するため、本発明は以下の構成を有する。
　使用者の手指の第一関節より先端側の指腹に取り付けられ、触診時に触診対象部位の酸素濃度を測定するための触診用近赤外酸素濃度センサであって、
　前記指腹に取り付けられる基材と、
　前記基材に設けられ、近赤外光を含む少なくとも２波長の光を被検体に照射する発光手段と、
　前記基材に設けられ、前記発光素子から前記被検体を経由した測定光を受光する受光手段と、
　少なくとも前記発光手段又は前記受光手段と前記指腹との間に設けられる遮光手段と、
を有する
触診用近赤外酸素濃度センサ。In order to solve the above problems, the present invention has the following configuration.
A near-infrared oxygen concentration sensor for palpation, which is attached to the finger pad on the tip side from the first joint of the user's finger and for measuring the oxygen concentration of the site to be palpated during palpation,
A base material attached to the finger pad;
A light emitting means that is provided on the substrate and irradiates the subject with light of at least two wavelengths including near infrared light;
A light receiving means provided on the base material for receiving measurement light from the light emitting element via the subject; and
Light shielding means provided at least between the light emitting means or the light receiving means and the finger pad;
A near infrared oxygen concentration sensor for palpation.

　前記手指は人差し指又は中指が好適に用いられ得るが、これに限定されるものではない。
　前記指腹は手指の第一関節より先端側で爪とは反対側の面で指紋がある部分である。
　前記基材は平板状の基板が好適に用いられ得るが、これに限定されるものではない。
　前記発光手段はＬＥＤが好適に用いられ得るが、これに限定されず、光ファイバなどで外部から導光しても構わない。
　前記発光手段から照射される光の波長は735nm及び870nmが好適に用いられ得るが、体内組織中の酸素濃度が測定できるものであればこれに限定されるものではない。
　前記受光手段はフォトダイオード又はフォトトランジスタが好適に用いられ得るが、これに限定されず、光ファイバなどを介在させて受光素子を離れたところに配置しても構わない。The index finger or the middle finger can be suitably used as the finger, but is not limited thereto.
The finger pad is a portion where there is a fingerprint on the surface on the tip side from the first joint of the finger and on the side opposite to the nail.
The substrate may be a flat substrate, but is not limited thereto.
As the light emitting means, an LED can be suitably used. However, the light emitting means is not limited to this, and the light emitting means may be guided from the outside by an optical fiber or the like.
The wavelength of light emitted from the light emitting means can be preferably 735 nm and 870 nm, but is not limited to this as long as the oxygen concentration in the body tissue can be measured.
A photodiode or a phototransistor can be suitably used as the light receiving means, but the light receiving means is not limited to this, and the light receiving element may be disposed at a distance from the optical fiber.

　前記遮光手段は、使用者の指を経由した測定光が受光手段に導かれないようにするものである。
　前記遮光手段については、使用者の指からの測定光を受光しないようにできれば材質は何でもよく、例えば黒色のゴム材などが用いられる。また、前記遮光手段は前記基材と別に設けても良いし、前記基材そのものが遮光性能を有していても良い。
　前記発光手段は１つでも良いし、複数でもよい。また、前記受光手段も１つでも良いし、複数でもよい。The light shielding means prevents the measurement light passing through the user's finger from being guided to the light receiving means.
The light shielding means may be made of any material as long as it does not receive the measurement light from the user's finger. For example, a black rubber material is used. The light shielding means may be provided separately from the base material, or the base material itself may have a light shielding performance.
There may be one or more light emitting means. Further, the light receiving means may be one or plural.

　前記発光手段と前記受光手段との間の最小距離が3mm以上であり、最大距離が15mm以下であることが好ましい。
　前記最小距離は、発光手段又は受光手段が複数ある場合は、最も距離の小さい発光手段と受光手段との組み合わせ間の距離であり、発光手段又は受光手段が所定の面積を有している場合は、発光手段と受光手段の端部間の最小距離である。
　前記最大距離は、発光手段又は受光手段が複数ある場合は、最も距離の大きい発光手段と受光手段との組み合わせ間の距離であり、発光手段又は受光手段が所定の面積を有している場合は、発光手段と受光手段の端部間の最大距離である。
　前記触診用近赤外酸素濃度センサの被検体と接触する面は、平坦でも良いし、発光手段や受光手段などが突出した凹凸構造を有していても良い。センサ表面が凹凸構造を有していると、触診の際に体毛（胎児の頭髪など）をかき分けて発光手段及び受光手段を被検体表面に接触させることができ、操作性が増す。一方で、測定対象部位によってはセンサ表面は平坦の方が良い場合もあり、用途に応じて最適な方を選択すれば良い。Preferably, the minimum distance between the light emitting means and the light receiving means is 3 mm or more, and the maximum distance is 15 mm or less.
The minimum distance is the distance between the combination of the light emitting means and the light receiving means having the shortest distance when there are a plurality of light emitting means or light receiving means, and the light emitting means or the light receiving means has a predetermined area. , The minimum distance between the ends of the light emitting means and the light receiving means.
The maximum distance is the distance between the combination of the light emitting means and the light receiving means having the longest distance when there are a plurality of light emitting means or light receiving means, and the light emitting means or the light receiving means has a predetermined area. The maximum distance between the ends of the light emitting means and the light receiving means.
The surface in contact with the subject of the near-infrared oxygen concentration sensor for palpation may be flat or may have a concavo-convex structure from which light emitting means, light receiving means, etc. protrude. When the sensor surface has a concavo-convex structure, body light (fetal hair, etc.) can be scraped off during palpation, and the light emitting means and the light receiving means can be brought into contact with the subject surface, thereby improving operability. On the other hand, depending on the region to be measured, the sensor surface may be flat, and an optimal one may be selected according to the application.

　本発明は、使用者の手指の第一関節より先端側の指腹に取り付けるための特有の構成を有しており、触診の操作性を損なわずにセンサ部分を体腔内の測定対象部位に接触させて当該部位の組織内の酸素濃度を測定することができる。具体的には、センサ部分（発光手段及び受光手段）の裏側（使用者の指側）に遮光手段を設けることにより、使用者の組織内から情報を遮断して、被検体からの情報のみを取得できるようにしている。また、指腹に取り付けるために、発光手段と受光手段との最大距離を15mm以下にすることが好ましい。発光手段と受光手段との間の距離は組織内の情報を取得するために一定距離以上で必要であり、特許文献１に対応する市販の胎児用パルスオキシメータ（NEELCOR社、Oxifirst）ではセンサ部分の長さは約40mmであるが、本発明では酸素濃度を演算するアルゴリズムに工夫を加えることにより最大距離15mm以下を実現している。さらに、本発明は触診用であるため一般的に近赤外線が透過する透明あるいは半透明の診察用手袋を着用して使用される。本発明では、発光手段と受光手段との間の最小距離を3mm以上にすることと、近赤外線が透過する手袋の使用により、発光手段からの光が手袋内を通って受光手段に直接導かれることを防いでいる。The present invention has a specific configuration for attaching to the finger pad on the distal end side from the first joint of the user's finger, and the sensor portion is brought into contact with the measurement target site in the body cavity without impairing the operability of palpation. Thus, the oxygen concentration in the tissue at the site can be measured. Specifically, by providing light shielding means on the back side (user finger side) of the sensor portion (light emitting means and light receiving means), information is blocked from the user's tissue, and only information from the subject is obtained. You can get it. In order to attach to the finger pad, the maximum distance between the light emitting means and the light receiving means is preferably 15 mm or less. The distance between the light emitting means and the light receiving means is required to be a certain distance or more in order to acquire information in the tissue. In the commercially available fetal pulse oximeter (NEELCOR, Oxifirst) corresponding toPatent Document 1, the sensor portion Is about 40 mm, but in the present invention, the maximum distance of 15 mm or less is realized by adding a device to the algorithm for calculating the oxygen concentration. Furthermore, since the present invention is for palpation, it is generally used by wearing transparent or translucent diagnostic gloves that transmit near infrared rays. In the present invention, by setting the minimum distance between the light emitting means and the light receiving means to 3 mm or more and using a glove that transmits near infrared rays, light from the light emitting means is directly guided to the light receiving means through the glove. It prevents that.

　本発明は、子宮内の胎児の頭皮に接触させて胎児の酸素濃度を測定するのに好適に用いられ得る。医師は分娩進行状態を診るために頻繁に内診を行い、内診の際には必ず胎児の頭皮に触れて診察をする。この際に、本発明の触診用近赤外酸素濃度センサを指先に取り付けることで、胎児の頭皮にセンサを確実に接触させることでき、胎児の酸素濃度を測定することができる。本発明のセンサは極めて小型であるので、通常の内診による診察と同じ手技で診察及び酸素濃度測定を行うことが可能である。The present invention can be suitably used for measuring the fetal oxygen concentration by contacting the fetal scalp in the uterus. Doctors frequently perform internal examinations to check the progress of labor, and always make a medical examination by touching the scalp of the fetus. At this time, by attaching the near-infrared oxygen concentration sensor for palpation of the present invention to the fingertip, the sensor can be reliably brought into contact with the scalp of the fetus, and the oxygen concentration of the fetus can be measured. Since the sensor of the present invention is extremely small, it is possible to perform a diagnosis and an oxygen concentration measurement by the same technique as a normal internal examination.

　なお本発明は、子宮内の胎児の他、医師が指で触れることが可能な部位であればどこにでも用いることができる。例えば、体腔内（口腔内、直腸など）の部位や、手術中の部位（例えば、心臓など）に用いることができる。心筋梗塞の手術中に用いれば、心臓のどこの部分の酸素濃度が低下しているかを把握することが可能である。そのほか、医師が手術中に触れることができる腹腔内や胸腔内のすべての臓器が対象になり、例えば、肝臓、胃、脾臓、膵臓、腸などが測定対象になり得る。また、口腔内や腋窩などで用いれば、脳に近い部分の酸素濃度を直接測定することができ、特に従来の指に装着するパルスオキシメータでは測定困難であった重篤患者の状態を素早く診断することができる。さらに、医師が触れながら部位を特定してその部位の酸素濃度を測定できることから、体表のどの部位の皮膚上からでも用いることができる。例えば、新生児の皮膚の部位別酸素動態の把握などにも用いることが可能である。It should be noted that the present invention can be used anywhere as long as the doctor can touch it with a finger in addition to the fetus in the uterus. For example, it can be used in a body cavity (in the oral cavity, rectum, etc.) or a site during surgery (for example, heart). If used during surgery for myocardial infarction, it is possible to determine where in the heart the oxygen concentration is reduced. In addition, all organs in the abdominal cavity and thoracic cavity that can be touched by the doctor during the operation are targeted. For example, the liver, stomach, spleen, pancreas, intestine, and the like can be measured. In addition, when used in the oral cavity, axilla, etc., it is possible to directly measure the oxygen concentration in the part close to the brain. In particular, it is possible to quickly diagnose the condition of severe patients that were difficult to measure with a conventional pulse oximeter attached to the finger. can do. Furthermore, since the site | part can be identified and the oxygen concentration of the site | part can be measured while a doctor touches, it can be used from the skin of any site | part of a body surface. For example, it can be used for grasping the oxygen dynamics of each part of the newborn's skin.

　また、本発明は以下の好ましい実施態様を有する。
　前記受光手段からの測定光に基づいて、前記被検体の酸素化ヘモグロビン濃度、脱酸素化ヘモグロビン濃度及び酸素飽和度の少なくともいずれか１つを算出する演算手段を有する。Moreover, this invention has the following preferable embodiments.
Computation means for calculating at least one of oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration and oxygen saturation of the subject based on the measurement light from the light receiving means.

　また、本発明は以下の好ましい実施態様を有する。
　前記発光手段及び前記受光手段の合計が３個以上であり、
　前記演算手段は、複数の発光手段－受光手段間距離の測定光に基づいて、前記被検体の酸素化ヘモグロビン濃度、脱酸素化ヘモグロビン濃度及び酸素飽和度の少なくともいずれか１つを算出する。
　発光手段と受光手段はそれぞれ１個以上あるので、発光手段と受光手段の合計が３個以上となる組み合わせは、発光手段が１個で受光手段が複数個、発光手段が複数個で受光手段が１個、又は、発光手段も受光手段も複数個があり得る。発光手段と受光手段の組み合わせは、好ましくは発光手段が１個で受光手段が複数個、さらに好ましくは発光手段が１個で受光手段が２個である。発光手段が複数個だと発光手段自体の素子のばらつきの影響を受けやすくなるので発光手段は１個で受光手段を複数個とするのが好ましい。Moreover, this invention has the following preferable embodiments.
The total of the light emitting means and the light receiving means is 3 or more,
The calculation means calculates at least one of oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration, and oxygen saturation of the subject based on a plurality of measurement lights of the distance between the light emitting means and the light receiving means.
Since there are one or more light emitting means and one light receiving means, the combination of three or more light emitting means and light receiving means is a combination of one light emitting means, a plurality of light receiving means, a plurality of light emitting means, and a light receiving means. There may be one or a plurality of light emitting means and light receiving means. The combination of the light emitting means and the light receiving means is preferably one light emitting means and a plurality of light receiving means, more preferably one light emitting means and two light receiving means. If there are a plurality of light emitting means, it is easy to be affected by variations in the elements of the light emitting means itself.

　本発明はパルスオキシメータとしても使用可能であるが、より好適には、特許文献２及び３に記載されているような、複数の発光手段－受光手段間距離の測定光に基づいて空間的傾きＳを求めて組織内の吸光度を求める演算が用いられ得る。パルスオキシメータでは脈動の大きな部分（例えば動脈など）の酸素濃度しか測れないが、空間的傾きＳを用いる演算であれば、脈動の小さい部分でも酸素濃度を測定することができ、体表組織などの酸素濃度をより確実に測定することができる。特に、低酸素血症の恐れがある胎児の酸素濃度の測定には有効である。さらに、空間的傾きＳを用いる演算では、酸素飽和度だけではなく、酸素化ヘモグロビン濃度と脱酸素化ヘモグロビン濃度の絶対値が測定できるため、より多くの診断情報を得ることができる。The present invention can also be used as a pulse oximeter, but more preferably, the spatial inclination based on the measurement light of the distances between the light emitting means and the light receiving means as described inPatent Documents 2 and 3. An operation for obtaining S to determine the absorbance in the tissue can be used. The pulse oximeter can measure only the oxygen concentration in a portion with a large pulsation (for example, an artery), but if the calculation uses the spatial slope S, the oxygen concentration can be measured even in a portion with a small pulsation, such as a body surface tissue. It is possible to more reliably measure the oxygen concentration. In particular, it is effective in measuring the fetal oxygen concentration, which may cause hypoxemia. Furthermore, in the calculation using the spatial gradient S, not only the oxygen saturation but also the absolute values of the oxygenated hemoglobin concentration and the deoxygenated hemoglobin concentration can be measured, so that more diagnostic information can be obtained.

　また、本発明は以下の好ましい実施態様を有する。
　前記発光手段と前記受光手段との間の最小距離が3mm以上であり、最大距離が15mm以下である。Moreover, this invention has the following preferable embodiments.
The minimum distance between the light emitting means and the light receiving means is 3 mm or more, and the maximum distance is 15 mm or less.

　また、本発明は以下の好ましい実施態様を有する。
　前記基材を前記指腹に固定する固定手段を有する。
　前記固定手段は、前記基材と前記指腹とを相対的に固定できるものであれば何でも良い。好適例としては、粘着テープにより固定する、バンドにより固定する、指に嵌める指サックに基材を固定する、などがある。また、前記固定手段が前記遮光手段を兼ねていても良い。Moreover, this invention has the following preferable embodiments.
A fixing means for fixing the base material to the finger pad;
The fixing means may be anything as long as it can relatively fix the base material and the finger pad. Preferable examples include fixing with an adhesive tape, fixing with a band, fixing a base material to a finger sack fitted on a finger, and the like. The fixing means may also serve as the light shielding means.

　また、本発明は以下の好ましい実施態様を有する。
　少なくとも、前記基材、前記発光手段及び前記受光手段を含む部分はディスポーザブルである。
　本発明のセンサは被検体の体腔内に挿入して用いられ得るため、少なくとも体腔内に挿入する部分についてはディスポーザブルにすることにより感染症の危険を防ぐことができる。Moreover, this invention has the following preferable embodiments.
At least the part including the base material, the light emitting means and the light receiving means is disposable.
Since the sensor of the present invention can be used by being inserted into the body cavity of the subject, the risk of infection can be prevented by disposing at least the part to be inserted into the body cavity.

　また、本発明は以下の好ましい実施態様を有する。
　前記触診用近赤外濃度センサは近赤外光を透過する手袋を着用して使用されるものであり、
　前記演算手段は、前記手袋による測定光への影響をキャンセルする手段を有する。
　近赤外光を透過する手袋は、例えば、透明又は白色で、プラスチック製やビニール製が用いられ得る。
　手袋を着用するとセンサ部と測定対象部位との間に手袋が介在することになる。パルスオキシメータでは脈動による変動分を算出しているので手袋による影響をキャンセルできる。空間的傾きＳを用いる演算では、発光手段と受光手段とが十分に離れていれば（3mm以上）、手袋による光の吸収量は距離に依存しなくなるので、複数の発光手段－受光手段間距離の測定光から手袋による影響を取り除くことができる。Moreover, this invention has the following preferable embodiments.
The near infrared density sensor for palpation is used by wearing gloves that transmit near infrared light,
The computing means has means for canceling the influence of the glove on the measuring light.
The gloves that transmit near-infrared light are, for example, transparent or white, and plastic or vinyl can be used.
When gloves are worn, the gloves are interposed between the sensor unit and the measurement target part. Since the pulse oximeter calculates the fluctuation due to pulsation, the effects of gloves can be canceled. In the calculation using the spatial inclination S, if the light emitting means and the light receiving means are sufficiently separated (3 mm or more), the amount of light absorbed by the glove does not depend on the distance. The effect of gloves can be removed from the measurement light.

　また、本発明は以下の好ましい実施態様を有する。
　前記発光手段及び前記受光手段に接続される信号ケーブルにはフラットケーブルが用いられる。Moreover, this invention has the following preferable embodiments.
A flat cable is used as the signal cable connected to the light emitting means and the light receiving means.

　本発明は上記構成により、触診用酸素濃度センサにおいて、触診の操作性への影響を最小限にしつつ、測定対象部位へのセンサの接触を確実にして、当該部位の酸素濃度（酸素化ヘモグロビン濃度、脱酸素化ヘモグロビン濃度、酸素飽和度など）を測定することができる。According to the present invention, in the oxygen concentration sensor for palpation, the oxygen concentration (oxygenated hemoglobin concentration) of the part is ensured in the palpation oxygen concentration sensor while ensuring the contact of the sensor with the part to be measured while minimizing the influence on the operability of palpation , Deoxygenated hemoglobin concentration, oxygen saturation, etc.) can be measured.

本発明の実施形態の正面図。The front view of the embodiment of the present invention.本発明の実施形態の側面図。The side view of the embodiment of the present invention.本発明の実施形態の外観図。1 is an external view of an embodiment of the present invention.本発明の実施形態のシステム図。1 is a system diagram of an embodiment of the present invention.本発明の実施形態における測定光伝搬経路の説明図。Explanatory drawing of the measurement light propagation path in embodiment of this invention.

　以下、図面とともに本発明に係る触診用近赤外酸素濃度センサの好適な実施形態について説明する。Hereinafter, preferred embodiments of the near-infrared oxygen concentration sensor for palpation according to the present invention will be described with reference to the drawings.

　図１は本実施形態の触診用近赤外酸素濃度センサの正面図、図２はセンサ本体１の側面図、図３は本実施形態の触診用近赤外酸素濃度センサを指に装着した際の外観図である。
　図３に示すように、センサ本体１は使用者（医師等）の手指の指腹１３（第一関節よりも先端側）に収まる形状及び大きさであり、使用者の指腹１３に固定される。センサ本体１からはフレキシブルなフラットケーブル７が導出されており、指の付け根より手のひら側のコネクタ（図示せず）に接続されている。フラットケーブルは指背を通すことも可能である。センサ本体１が使用者の指腹１３に収まる形状及び大きさであるので、使用者は触診による感覚や操作性を損なうことなく、触っている部位の酸素濃度を測定することができる。実際に使用する際には、診察などに用いられる手袋を着用して使用する。手袋は近赤外線を透過できるものであれば良く、透明、半透明、白色のものが用いられる。1 is a front view of a near-infrared oxygen concentration sensor for palpation according to the present embodiment, FIG. 2 is a side view of the sensormain body 1, and FIG. 3 is a diagram when the near-infrared oxygen concentration sensor for palpation according to the present embodiment is attached to a finger. FIG.
As shown in FIG. 3, the sensormain body 1 has a shape and a size that fits on thefinger pad 13 of the finger of the user (doctor or the like) (on the tip side of the first joint), and is fixed to thefinger pad 13 of the user. The A flexibleflat cable 7 is led out from thesensor body 1 and connected to a connector (not shown) on the palm side from the base of the finger. The flat cable can be passed through the back of the finger. Since thesensor body 1 has a shape and size that fits in thefinger pad 13 of the user, the user can measure the oxygen concentration of the touched part without impairing the sense and operability of palpation. In actual use, wear gloves used for medical examinations. The glove is not particularly limited as long as it can transmit near-infrared rays, and transparent, translucent, and white are used.

　図１及び図２に示すように、センサ本体１は、基板２と、基板２の裏面側に設けられた遮光体３と、基板２に配置された発光素子４と、基板２に配置され発光素子４とは所定の距離離れて配置された第１受光素子５ａと、基板２に配置され発光素子４に対して第１受光素子５ａよりも離れて配置された第２受光素子５ｂと、発光素子４と第１受光素子５ａとの間に配置された第１遮光壁６ａ及び第２遮光壁６ｂ、とからなる。センサ本体１の基板２にはフラットケーブル７が接続されており後ほど説明するセンサ制御装置８に接続されている。As shown in FIGS. 1 and 2, thesensor body 1 includes asubstrate 2, alight shield 3 provided on the back side of thesubstrate 2, alight emitting element 4 disposed on thesubstrate 2, and light emission disposed on thesubstrate 2. A firstlight receiving element 5a disposed at a predetermined distance from theelement 4, a secondlight receiving element 5b disposed on thesubstrate 2 and disposed away from the firstlight receiving element 5a with respect to thelight emitting element 4, and light emission It consists of the 1stlight shielding wall 6a and the 2ndlight shielding wall 6b arrange | positioned between theelement 4 and the 1stlight receiving element 5a. Aflat cable 7 is connected to thesubstrate 2 of thesensor body 1 and is connected to asensor control device 8 which will be described later.

　基板２は材質としてエポキシやポリイミドなどが用いられる。被検体表面への接触性を良くするためフレキシブルな基板が好ましいが、センサ本体１が十分に小さければ硬性の基板でも構わない。大きさは使用者の指腹に収まる大きさであればいいが、本実施形態では長さ約10mm、幅約5mmである。
　遮光体３は、使用者の指の酸素濃度情報がセンサ本体１に届かないようにするためものである。センサ本体１は薄く、また使用者の指に取り付けられるため、使用者の指に発光素子４からの光が照射されてしまう可能性がある。照射された光が受光素子５で受光されると使用者の酸素濃度情報も混ざってしまう。そのために、センサ本体１と使用者の指腹との間に遮光体３を設けて、使用者の指からの光情報を遮蔽する。使用者の指からの測定光が受光素子５に届かなければ良いため、発光素子４の裏側だけを遮蔽する、受光素子５の裏側だけを遮蔽する、基板２の裏面全面を遮蔽するなどの種々の配置が考えられる。また、基板２に遮光材料を用いることで基板２自体が遮光体を兼ねても良い。本実施形態では、遮光体３の材質として黒色のゴム材を用いているが、遮光性能をもつ材質であればこれに限られない。Thesubstrate 2 is made of epoxy or polyimide as a material. A flexible substrate is preferable in order to improve the contact property to the surface of the subject, but a rigid substrate may be used if thesensor body 1 is sufficiently small. The size may be any size as long as it fits in the user's finger pad, but in this embodiment, the length is about 10 mm and the width is about 5 mm.
Thelight shield 3 is for preventing oxygen concentration information of the user's finger from reaching thesensor body 1. Since thesensor body 1 is thin and attached to the user's finger, there is a possibility that the light from thelight emitting element 4 may be irradiated to the user's finger. When the irradiated light is received by the light receiving element 5, the oxygen concentration information of the user is also mixed. For this purpose, alight shield 3 is provided between thesensor body 1 and the user's finger pad to shield light information from the user's finger. Since the measurement light from the user's finger does not have to reach the light receiving element 5, various measures such as shielding only the back side of thelight emitting element 4, shielding only the back side of the light receiving element 5, and shielding the entire back surface of thesubstrate 2. Can be considered. Further, by using a light shielding material for thesubstrate 2, thesubstrate 2 itself may also serve as a light shielding body. In the present embodiment, a black rubber material is used as the material of thelight shielding body 3, but the material is not limited to this as long as the material has a light shielding performance.

　発光素子４は、本実施形態では735nmと870nmの波長の光を照射するＬＥＤを用いている。少なくとも２波長の光を被検体内部に照射できる光源であれば何でも良い。
　受光素子５は、本実施形態ではフォトダイオードを用いており、発光素子４と第１受光素子５ａとの間（第１距離ｄ_１）は約6mm、発光素子４と第２受光素子５ｂとの間（第２距離ｄ_２）は約8mmである。受光素子５は、被検体内部からの光を受光できるものであれば何でも良い。
　遮光壁６は、発光素子４と受光素子５との間に設けられ、発光素子４からの直接光が受光素子５で検出されるのを防ぐためのもので、本実施形態では、発光素子４に近い側に第１遮光壁６ａが配置されており、第１受光素子５ａに近い側に第２遮光壁６ｂが配置されている。In the present embodiment, thelight emitting element 4 is an LED that emits light having wavelengths of 735 nm and 870 nm. Any light source capable of irradiating at least two wavelengths of light into the subject may be used.
In the present embodiment, the light receiving element 5 uses a photodiode, and the distance between the light emittingelement 4 and the firstlight receiving element 5a (first distance d₁ ) is about 6 mm, and thelight receiving element 4 and the secondlight receiving element 5b The distance (second distance d₂ ) is about 8 mm. The light receiving element 5 may be anything as long as it can receive light from inside the subject.
The light shielding wall 6 is provided between the light emittingelement 4 and the light receiving element 5 to prevent direct light from thelight emitting element 4 from being detected by the light receiving element 5. In the present embodiment, thelight emitting element 4 The firstlight shielding wall 6a is disposed on the side close to the first light receiving wall, and the secondlight shielding wall 6b is disposed on the side closer to the firstlight receiving element 5a.

　フラットケーブル７は、電子回路の接続などに用いられるもので、例えばポリイミドなどが用いられる。基板２にコネクタ等で接続しても良いし、基板２と一体でも良い。フラットケーブル７のセンサ本体１とは反対側の端部は、指の付け根より先の掌部にあるコネクタ（図示せず）に接続される。コネクタの位置は触診の邪魔にならなければどこでも良く、掌の先の腕の部分に設けても良い。コネクタから先は、後ほど説明するセンサ制御装置８に接続される。本実施形態では、フラットケーブル７の幅は約3mmである。Theflat cable 7 is used for connecting an electronic circuit, for example, polyimide. It may be connected to thesubstrate 2 with a connector or the like, or may be integrated with thesubstrate 2. The end portion of theflat cable 7 opposite to thesensor body 1 is connected to a connector (not shown) in the palm portion beyond the base of the finger. The position of the connector may be anywhere as long as it does not interfere with palpation, and may be provided on the arm at the tip of the palm. The connector is connected to thesensor control device 8 which will be described later. In the present embodiment, theflat cable 7 has a width of about 3 mm.

　図４を用いて本実施形態のシステム構成について説明する。本実施形態の近赤外酸素濃度測定システムは、センサ本体１に接続されセンサ本体１を制御するセンサ制御装置８と、センサ制御装置８に接続されセンサ制御装置８からの信号を解析し酸素濃度等の算出を行う演算装置９と、演算装置９により算出された酸素濃度等を表示する表示デバイス１０と、演算装置９にパラメータなどを入力する入力デバイス１１からなる。The system configuration of this embodiment will be described with reference to FIG. The near-infrared oxygen concentration measurement system according to the present embodiment includes asensor control device 8 connected to thesensor body 1 and controlling thesensor body 1, and a signal connected to thesensor control device 8 and analyzed from thesensor control device 8 to analyze the oxygen concentration. And the like, adisplay device 10 that displays the oxygen concentration calculated by thearithmetic device 9, and aninput device 11 that inputs parameters and the like to thearithmetic device 9.

　センサ制御装置８は、発光素子４を駆動するドライバ、受光素子５からの信号を増幅する増幅器などを有している。発光素子４の発光タイミングや受光素子５の受光タイミングはセンサ制御装置８で制御しても良いし、演算装置９で制御しても良い。受光素子５からのアナログ信号のデジタル化も、センサ制御装置８、演算装置９のいずれで行っても構わない。Thesensor control device 8 includes a driver for driving thelight emitting element 4 and an amplifier for amplifying a signal from the light receiving element 5. The light emission timing of thelight emitting element 4 and the light reception timing of the light receiving element 5 may be controlled by thesensor control device 8 or thearithmetic device 9. Digitization of the analog signal from the light receiving element 5 may be performed by either thesensor control device 8 or thearithmetic device 9.

　演算装置９にはＰＣ（パーソナルコンピュータ）などが用いられるが、センサ制御装置８と一体化して専用機にしても良い。演算装置９では、脈動による吸光度の変動分から酸素飽和度等を求めるパルスオキシメータ法を用いても良いし、後述する空間的傾きを利用して酸素化ヘモグロビン濃度、脱酸素化ヘモグロビン濃度、酸素飽和度等を求める空間的傾き法を用いても良い。表示デバイス１０は演算結果を表示できるものであれば何でも良く、ＬＣＤなどが用いられる。入力デバイス１１も入力できるデバイスであれば何でも良く、キーボード、マウス、タッチパネルなどが用いられる。A PC (personal computer) or the like is used as thearithmetic device 9, but it may be integrated with thesensor control device 8 to be a dedicated machine. Thearithmetic unit 9 may use a pulse oximeter method for obtaining an oxygen saturation or the like from a change in absorbance due to pulsation, or an oxygenated hemoglobin concentration, a deoxygenated hemoglobin concentration, an oxygen saturation using a spatial gradient described later. A spatial tilt method for obtaining degrees or the like may be used. Thedisplay device 10 may be anything as long as it can display the calculation result, and an LCD or the like is used. Theinput device 11 may be any device that can input, and a keyboard, a mouse, a touch panel, or the like is used.

　図５を用いて本実施形態で好適に用いられる酸素濃度算出方法である空間的傾き法について説明する。本アルゴリズムの演算は、演算装置９で実行される。
　発光素子４から照射された光は、手袋１２内の光路ａ_０を通過し、被検体の組織に照射される。被検体の組織に照射された光は、組織内で吸収・散乱されて光路ｂ_１及び光路ｂ_２を経由し、手袋１２内の光路ａ_１及び光路ａ_２を通過して、第１受光素子５ａ及び第２受光素子５ｂで受光される。図面では便宜上、光路ｂ_１及び光路ｂ_２を線状に記載しているが、実際には組織内を散乱しながら伝搬していくので光路は複雑である。遮光体３は使用者の指側に設けられ、発光素子４からの照射光が使用者の指組織を伝搬して受光素子５に導かれることを防いでいる。A spatial gradient method, which is an oxygen concentration calculation method suitably used in this embodiment, will be described with reference to FIG. The calculation of this algorithm is executed by thecalculation device 9.
The light irradiated from thelight emitting element 4 passes through the optical path a₀ in theglove 12 and is irradiated to the tissue of the subject. The light irradiated to the tissue of the subject is absorbed and scattered in the tissue, passes through the optical path b₁ and the optical path b_2, passes through the optical path a₁ and the optical path a₂ in theglove 12, and then the first light receiving element. The light is received by 5a and the secondlight receiving element 5b. In the drawing, for convenience, the optical path b₁ and the optical path b₂ are illustrated in a linear shape, but in reality, the light path is complicated because it propagates while being scattered in the tissue. The light-shieldingbody 3 is provided on the user's finger side to prevent the irradiation light from the light-emittingelement 4 from being propagated through the user's finger tissue and guided to the light-receiving element 5.

　空間的傾き法は、本願発明者の一人が、人間の組織内の光の吸収係数を空間的傾きＳの関数で表せることを、拡散理論や各種シミュレーション等により見出したものであり、詳細は特許文献２及び３に記載されている。
　第１受光素子５ａでの受光強度をＩ_１、第２受光素子５ｂでの受光強度をＩ_２、発光素子４と第１受光素子５ａとの間の距離をｄ_１、発光素子４と第２受光素子５ｂとの間をｄ_２とすると、空間的傾きＳは、
　　Ｓ＝ｌｎ（Ｉ_１／Ｉ_２）／（ｄ_２－ｄ_１）　　…（１）
で定義される。
　ｄ_１及びｄ_２は既知であるので、測定によりＩ_１とＩ_２の比を求めれば、空間的傾きＳが求まる。空間的傾きＳが求まれば、ルックアップテーブルなどを用いて組織内の光の吸収係数が求まるため、波長別の吸収係数を求めれば、酸素化ヘモグロビン濃度と脱酸素化ヘモグロビン濃度が算出でき、酸素化ヘモグロビン濃度と脱酸素化ヘモグロビン濃度の比である酸素飽和度も算出できる。なお、本実施形態では従来に比べて発光素子４と受光素子５との間の距離が短いため（例えば、15mm以下）、輸送理論を利用した改良アルゴリズムを利用しても良い。The spatial gradient method was found by diffusion theory and various simulations that one of the inventors of the present application can express the light absorption coefficient in human tissue as a function of the spatial gradient S. Documents 2 and 3 describe.
I₁ the received light intensity of the first light receiving element_5a, d₁ the distance between the received light intensity in the secondlight receiving element 5b I_2, thelight emitting element 4 and the first light receiving element_5a, thelight emitting element 4 and the second When d₂ is between thelight receiving element 5b and the spatial inclination S,
S = ln (I₁ / I₂ ) / (d₂ −d₁ ) (1)
Defined by
Since d₁ and d₂ are known, if the ratio of I₁ and I₂ is obtained by measurement, the spatial slope S is obtained. If the spatial gradient S is obtained, the absorption coefficient of light in the tissue is obtained using a lookup table or the like. Therefore, if the absorption coefficient for each wavelength is obtained, the oxygenated hemoglobin concentration and the deoxygenated hemoglobin concentration can be calculated, It is also possible to calculate the oxygen saturation, which is the ratio between the oxygenated hemoglobin concentration and the deoxygenated hemoglobin concentration. In the present embodiment, since the distance between the light emittingelement 4 and the light receiving element 5 is shorter than that in the prior art (for example, 15 mm or less), an improved algorithm using the transport theory may be used.

　本実施形態の触診用近赤外酸素濃度センサは、実際の使用形態では手袋１２を着用して用いられる。手袋１２は図５のように発光素子４及び受光素子５との間に介在し、受光信号に影響を与える。しかしながら、発光素子４と受光素子５との間の距離を十分にとれば（例えば、3mm以上）、光路ａ_０、光路ａ_１及び光路ａ_２は、いずれも発光面及び受光面に垂直であり、これらの光路長は同じ長さとみなせる。これらの情報を用いれば手袋１２の影響をキャンセルすることが可能である。The near-infrared oxygen concentration sensor for palpation of this embodiment is used by wearinggloves 12 in an actual usage pattern. Theglove 12 is interposed between the light emittingelement 4 and the light receiving element 5 as shown in FIG. 5 and affects the light reception signal. However, if the distance between the light emittingelement 4 and the light receiving element 5 is sufficiently long (for example, 3 mm or more), the optical path a₀ , the optical path a_1, and the optical path a₂ are all perpendicular to the light emitting surface and the light receiving surface. These optical path lengths can be regarded as the same length. If these pieces of information are used, it is possible to cancel the influence of thegloves 12.

　以上、本発明の実施形態の一例を説明したが、本発明はこれに限定されるものではなく、特許請求の範囲に記載された技術的思想の範疇において各種の変更が可能であることは言うまでもない。Although an example of the embodiment of the present invention has been described above, the present invention is not limited to this, and it goes without saying that various modifications can be made within the scope of the technical idea described in the claims. Yes.

　１：センサ本体、２：基板、３：遮光体、４：発光素子、５ａ：第１受光素子、５ｂ：第２受光素子、６ａ：第１遮光壁、６ｂ：第２遮光壁、７：フラットケーブル、８：センサ制御装置、９：演算装置、１０：表示デバイス、１１：入力デバイス、１２：手袋、１３：指腹

 1: sensor body, 2: substrate, 3: light shield, 4: light emitting element, 5a: first light receiving element, 5b: second light receiving element, 6a: first light shielding wall, 6b: second light shielding wall, 7: flat Cable: 8: Sensor control device, 9: Computing device, 10: Display device, 11: Input device, 12: Gloves, 13: Finger pad

Claims (8)

1. 　使用者の手指の第一関節より先端側の指腹に取り付けられ、触診時に触診対象部位の酸素濃度を測定するための触診用近赤外酸素濃度センサであって、
   　前記指腹に取り付けられる基材と、
   　前記基材に設けられ、近赤外光を含む少なくとも２波長の光を被検体に照射する発光手段と、
   　前記基材に設けられ、前記発光素子から前記被検体を経由した測定光を受光する受光手段と、
   　少なくとも前記発光手段又は前記受光手段と前記指腹との間に設けられる遮光手段と、を有する
   触診用近赤外酸素濃度センサ。A near-infrared oxygen concentration sensor for palpation, which is attached to the finger pad on the tip side from the first joint of the user's finger and for measuring the oxygen concentration of the site to be palpated during palpation,
   A base material attached to the finger pad;
   A light emitting means that is provided on the substrate and irradiates the subject with light of at least two wavelengths including near infrared light;
   A light receiving means provided on the base material for receiving measurement light from the light emitting element via the subject; and
   A near-infrared oxygen concentration sensor for palpation comprising at least the light emitting means or the light shielding means provided between the light receiving means and the finger pad.
2. 　前記受光手段からの測定光に基づいて、前記被検体の酸素化ヘモグロビン濃度、脱酸素化ヘモグロビン濃度及び酸素飽和度の少なくともいずれか１つを算出する演算手段を有する
   請求項１記載の触診用近赤外酸素濃度センサ。The palpation proximity according to claim 1, further comprising calculation means for calculating at least one of oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration, and oxygen saturation of the subject based on measurement light from the light receiving means. Infrared oxygen concentration sensor.
3. 　前記発光手段及び前記受光手段の合計が３個以上であり、
   　前記演算手段は、複数の発光手段－受光手段間距離の測定光に基づいて、前記被検体の酸素化ヘモグロビン濃度、脱酸素化ヘモグロビン濃度及び酸素飽和度の少なくともいずれか１つを算出する
   請求項１又は２記載の触診用近赤外酸素濃度センサ。The total of the light emitting means and the light receiving means is 3 or more,
   The calculation means calculates at least one of an oxygenated hemoglobin concentration, a deoxygenated hemoglobin concentration, and an oxygen saturation level of the subject based on a plurality of measurement lights at a distance between the light emitting means and the light receiving means. The near-infrared oxygen concentration sensor for palpation according to 1 or 2.
4. 　前記発光手段と前記受光手段との間の最小距離が3mm以上であり、最大距離が15mm以下である
   請求項１乃至３いずれか記載の触診用近赤外酸素濃度センサ。The near-infrared oxygen concentration sensor for palpation according to any one of claims 1 to 3, wherein a minimum distance between the light emitting means and the light receiving means is 3 mm or more and a maximum distance is 15 mm or less.
5. 　前記基材を前記指腹に固定する固定手段を有する
   請求項１乃至４いずれか記載の触診用近赤外酸素濃度センサ。The near-infrared oxygen concentration sensor for palpation according to any one of claims 1 to 4, further comprising fixing means for fixing the base material to the finger pad.
6. 　少なくとも、前記基材、前記発光手段及び前記受光手段を含む部分はディスポーザブルである
   請求項１乃至５いずれか記載の触診用近赤外酸素濃度センサ。The near-infrared oxygen concentration sensor for palpation according to any one of claims 1 to 5, wherein at least a portion including the base material, the light emitting means, and the light receiving means is disposable.
7. 　前記触診用近赤外濃度センサは近赤外光を透過する手袋を着用して使用されるものであり、
   　前記演算手段は、前記手袋による測定光への影響をキャンセルする手段を有する
   請求項１乃至６いずれか記載の触診用近赤外酸素濃度センサ。The near infrared density sensor for palpation is used by wearing gloves that transmit near infrared light,
   The near-infrared oxygen concentration sensor for palpation according to any one of claims 1 to 6, wherein the calculation means includes means for canceling the influence of the gloves on the measurement light.
8. 　前記発光手段及び前記受光手段に接続される信号ケーブルにはフラットケーブルが用いられる
   請求項１乃至７いずれか記載の触診用近赤外酸素濃度センサ。
   
    The near infrared oxygen concentration sensor for palpation according to any one of claims 1 to 7, wherein a flat cable is used as a signal cable connected to the light emitting means and the light receiving means.
   
   

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